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By Krueger Systems, Inc.

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iCircuit is the easiest way to design and experiment with circuits. Its advanced simulation engine can handle both analog and digital circuits and features realtime always-on analysis. It is the perfect companion to students, hobbyists, and engineers.

You use it as you would any CAD program: you add elements, connect them together, and set their properties. But iCircuit is unlike other CAD programs because it is always simulating. It's just like working with the real circuit. You do not stop to take a measurement or spend a lot of time configuring reports. Instead, you just play with the circuit as you normally would, with the power on!

There are over 30 elements you can use to build your circuits. The app has everything from simple resistors, to switches, to MOSFETS, to digital gates.

The app features a multimeter that you use to probe around the circuit to instantly read voltages and currents. If you want to see how a value changes over time, then you can add values to the built-in oscilloscope. The scope can simultaneously track many signals over time and features a variety of automatic modes that make it easy for you to grasp the behavior of your circuit.

You can even export your circuits and PNGs, PDFs, and SVG files so that they are easy to include in reports or web sites. Scope data can even be exported for offline analysis.

See a tutorial videos at:

Supported elements include:

• Signal generators, Voltage sources, and Current sources
• Resistors, Capacitors, Inductors, Potentiometers, Regulators
• SPST/SPDT Switches, Relays, and Transformers
• Diodes, BJ Transistors, and MOSFETs
• Speakers, Microphones, Buzzers, DC Motors, and LEDs
• Op-amps, ADCs, and DACs
• Logic gates: AND, OR, NAND, NOR, XOR
• JK and D Flip-flops
• Over 30 74XX series ICs

What's New in Version 1.8.1

• Fixes a critical bug that prevented OS X Mavericks users from using the app
• Fixes the Insert menu and Undo

From the previous release notes:
• Addition of in-circuit gauges to always have measurements on the screen
• Addition of 6 CMOS ICs (4000, 4001, 4002, 4011, 4017, 4051, keep requesting on the uservoice!)
• Improved wire selection
• 64-bit support
• Lots of bug fixes


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Customer Reviews

Good basic teaching / learning tool

Mostly keyboard driven; needs contextual menus for basic component rename and so forth. Delete key does nothing; only backspace works, where delete is the obvious key to… delete… something. Needs a “test point” component. Needs (a lot) more digital components, there are only 18. No adders, no ALUs, no selectors like 3-to-8’s, etc. The more, the merrier, eh? Needs a little bit more lively simulation of things like lamps; they should light, I think, and buzzers should buzz, speakers should speak, etc. Be nice if an overloaded component smoked, too. 1/4 watt resistor with 5w power dissipation? Sizzle… ! :) But you don’t get to set the wattage of the component, so… this is a significant issue in terms of realism. One thing in particular that would be *lovely* is if you could drag values; for instance, say you want to DC bias a BJT NPN transistor’s collector 1/2 way between vcc and ground. Okay, so set the hFE as desired, put a resistor from the base to vcc, set a couple limits like 1k and 500k, now drag a slider and watch the scope. bingo, ultra-convenient bias setting. That kind of thing would make this into a deisgn tool, even if a very simple one. It would also be educational.

Overall, this is really fun, and I’m really comfortable using it to teach the basics. But it could be a great deal more, and I hope that at some point, it is. Well worth the price.

Great, but needs to be updated more frequently

I’m an electronics technician, with 38 years of experience in the industry. This app is nothing short of fantastic! This is perfect for students, techs, and engineers at all levels. For the price, you get a lot of stuff, truly a fine value. My only two complaints: 1. For an AC source, you can only adjust phase to 180 degrees. You cannot do a full 360 degrees. Reason, unknown. 2. The app is not updated frequently enough. Note to developer: More than a year between updates, gives the impression that the app has been abandoned. Try to do more frequent updates, even if it is just very minor. I have shown this to some experienced engineers, and their jaws drop.

Unreliable for real applications

Pros: No Ads!

Cons: It doesn’t work!

This app is very unstable and only works sometimes. Every time I make a change to the circuit the emulator doesn’t give a response (i.e. observed voltage change when a resistor value is changed). I have to save the file close and reopen to see the response I was looking for. Sometimes, I just get a convergence error and the circuit doesn’t work, but it worked previously. Now its not even letting me save my circuit, prompting me to write this frusturated review. A good concept, but you cant rely on this app to give you accurate results. Don’t waste your money.

View in Mac App Store
  • $9.99
  • Category: Productivity
  • Updated:
  • Version: 1.8.1
  • Size: 3.9 MB
  • Language: English
  • Seller:

Compatibility: OS X 10.6 or later, 64-bit processor

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